System for Forming a Movable Slab Foundation

ABSTRACT

A system for forming a movable slab foundation has a slab foundation, a support pier, and a housing positioned within the support pier. A support sleeve is positioned within and is substantially surrounded by the housing. Portions of the support sleeve are encased within the slab foundation. The support sleeve is capable of axial movement relative to the housing. A guide plate is connected to the lower end of the support sleeve. A cavity is defined by the space between the guide plate and the lower end of the housing. A port is located in and extends through the guide plate and into the cavity. The slab foundation, the support sleeve, and the guide plate are raised to a desired height relative to the housing. The cavity is filled with support media through the port to secure the position of the slab foundation, the support sleeve, and the guide plate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. Provisional Patent Application No. 61/262,454, filed on Nov. 18, 2009, and herein incorporated by reference in its entirety.

FIELD OF THE INVENTION

This invention relates in general to forming an adjustable foundation, and in particular, to a concrete slab foundation capable of being raised above the ground.

BACKGROUND OF THE INVENTION

Many structures have been built on foundations or slabs made of concrete poured on top of soil. Constant changes in the weather and moisture levels in the soil frequently cause damage to such a foundation. In many instances, the foundation may buckle or even crack. This phenomenon occurs for a variety of reasons, including uneven changes in the water content of supporting soils, uneven compacting of soils, and uneven loads being placed on soils. Over time, uneven movement in the soils under a foundation can cause a foundation to bend or crack.

Therefore, it would be desirable to provide a method and apparatus that would allow a foundation to be poured on top of soil and subsequently raised to a desired height to eliminate potential problems caused by soil movement and/or problematic soils.

SUMMARY OF THE INVENTION

An embodiment of the system for forming a movable slab foundation as comprised by the present invention has a slab foundation, at least one support pier, and at least one housing positioned within the at least one support pier. The at least one housing has an open upper end and a closed lower end. At least one support sleeve is positioned within and is substantially surrounded by the at least one housing. Portions of the at least one support sleeve are encased within the slab foundation. The at least one support sleeve is capable of movement relative to the at least one housing. A guide plate is connected to the at least one support sleeve. The outer peripheries of the guide plate engage the inner surfaces of the at least one housing. A cavity is defined by the space between the lower surface of the guide plate and the lower end of the at least one housing. At least one port is located in and extends through the guide plate and into the cavity.

An embodiment of the system for forming a movable slab foundation as comprised by the present invention has a slab foundation and at least one support pier. A first cylinder with an open upper end and a closed lower end is positioned within the at least one support pier. A second cylinder with a diameter less than the diameter of the first cylinder is surrounded by the first cylinder. An interstitial space is defined by the space between the first cylinder and the second cylinder. The lower end of the second cylinder is connected to the closed lower end of the first cylinder. Lower portions of at least one support sleeve are positioned in the interstitial space between the first cylinder and the second cylinder. Upper portions of the at least one support sleeve are encased within the slab foundation. The at least one support sleeve is capable of movement relative to the at least one housing. A guide plate is connected to the at least one support sleeve and is positioned within the interstitial space between the first cylinder and the second cylinder. The outer peripheries of the guide plate engage the inner surfaces of the first cylinder. An aperture is located in and extends through the guide plate. The second cylinder extends through the aperture, and thus, the guide plate surrounds the second cylinder. A cavity is defined by the space between the lower surface of the guide plate and the closed lower end of the first cylinder. At least one port is located in and extends through the guide plate and into the cavity. A lifting device is connected to the at least one support sleeve to move the at least one support sleeve and the slab foundation axially along the length of the first cylinder and the second cylinder.

An embodiment of the present invention is directed to a method for forming a movable slab foundation. The method comprises providing a housing with a closed lower end and an open upper end. A guide plate is positioned within and surrounded by the housing. The outer peripheries of the guide plate are engaged with the inner surfaces of the housing. A cavity is defined by the space between the closed lower end of the housing and the lower surface of the guide plate. A support sleeve is connected to the upper surface of the guide plate, and a port is located in and extends through the guide plate and into the cavity. A support pier is placed below an intended slab foundation area. The housing, the guide plate, and the support sleeve are positioned within the support pier. A slab foundation is formed such that it encases a portion of the support sleeve. The support sleeve, the guide plate, and the slab foundation are raised upwards relative to the housing to a desired height. The cavity is filled with a support media through the port to support the weight of the support sleeve, the guide plate, and the slab, thereby securing the position of the support sleeve, the guide plate, and the slab relative to the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the features and benefits of the invention, as well as others which will become apparent, may be understood in more detail, a more particular description of the invention briefly summarized above may be had by reference to the embodiments thereof which are illustrated in the appended drawings, which form a part of this specification. It is also to be noted, however, that the drawings illustrate only various embodiments of the invention and are therefore not to be considered limiting of the invention's scope as it may include other effective embodiments as well.

FIG. 1 is a sectional view of a single slab support, illustrating a concrete pier, a slab, and a lifting assembly.

FIG. 2 is a sectional view of the single slab support with the cylinder portion of the lifting assembly encased therein.

FIG. 3 is a sectional view of the cylinder portion of the lifting assembly taken along the line 3-3 of FIG. 2.

FIG. 4 is a sectional view of the piston portion of the lifting assembly.

FIG. 5 is a sectional view of the lifting assembly taken along the line 5-5 of FIG. 1.

FIG. 6 is a sectional view of the single slab support with a lifting rod inserted into the lifting assembly, and a lifting device and attachment rods connected.

FIG. 7 is a sectional view of the single slab support with the slab raised a portion from a ground surface.

FIG. 8 is a sectional view of the single slab support with the slab raised to a final height.

DETAILED DESCRIPTION OF THE INVENTION

The present invention now will be described more fully hereinafter with reference to the accompanying drawings in which a preferred embodiment of the invention is shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiment set forth herein; rather, this embodiment is provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.

Referring to FIG. 1, a foundation slab 11 may be used to support a house or other building. In this embodiment, the slab 11 is of concrete and initially rests on a ground surface 12 and a support surface or pier 13. The foundation or slab 11 is typically supported by a plurality of support surfaces or piers 13, but for simplification purposes, the single pier 13 will be discussed. In this embodiment, the pier 13 is of concrete and has a lifting assembly 14 embedded therein. The lifting assembly 14 comprises a cylinder portion 15 embedded within the pier 13 and a piston portion 16 positioned within the cylinder portion 15.

Referring to FIGS. 2 and 3, the cylinder portion 15 of the lifting assembly 14 (FIG. 1) comprises an outer cylindrical tube or pipe 17 and an inner cylindrical tube or pipe 19. The bottom ends of both the outer pipe 17 and the inner pipe 19 are connected to a base plate 21. In an embodiment, the base plate 21 may have an anchor bolt or other support members that extend a select distance into the concrete pier 13. The outer pipe 17 has an inner diameter that is greater than the outer diameter of the inner pipe 19, thereby forming an annular space between the outer pipe 17 and the inner 19 pipe. In an embodiment, the outer pipe 17 may be constructed of PVC pipe. However, in alternate embodiments, the outer pipe 17 may be constructed of other materials, for example, steel. In an embodiment, the inner pipe 19 may be constructed of steel.

Referring to FIG. 2, in an embodiment, the hole for the pier 13 is dug with a diameter such that the cylinder portion 15 of the lifting assembly 14 (FIG. 1) is fully encased within the concrete. Once the hole is dug, the pier 13 is formed by pouring concrete into the hole. The cylinder portion 15 is then embedded in the concrete of the pier 13 such that the uppermost ends of the cylinder portion 15 are substantially parallel with the ground surface 12. As previously discussed, in an embodiment, an anchor bolt or other support members may be connected to the base plate 21 and extend into the concrete of the pier 13 a distance below the base plate 21.

Referring to FIG. 4, the piston portion 16 of the lifting assembly 14 (FIG. 1) comprises a support sleeve or pipe 25. The lower end of the support sleeve or pipe 25 is connected to a guide plate 27. The support sleeve 25 has a diameter that is less than the diameter of the outer pipe 17 and greater than the diameter of the inner pipe 19 of the cylinder portion 15 (FIG. 1). The guide plate 27 has a large aperture 29 located in and extending axially through its center. The aperture 29 has a diameter that is slightly larger than the diameter of the inner pipe 19, thereby allowing the guide plate 27 and the piston portion 16 to slide over and down the inner pipe 19, within the cylinder portion 15 (FIG. 1). A plurality of ports 31 are located in and extend axially through the guide plate 27 between the aperture 29 and the support sleeve 25. In this embodiment, two ports 31 are positioned one hundred and eighty (180) degrees apart (FIG. 5).

The length of the support sleeve 25 may be varied depending upon the desired final height of the slab foundation 11. Reinforcing bars (rebar) 33 are connected to the outer surface of the sleeve 25. In this embodiment, a first leg 35 of the rebar 33 is connected to the outer surface of the sleeve 25 and extends parallel to the axis of the sleeve 25. A second leg 37 of the rebar 33 extends outwardly and downwardly at an angle from a bottom end of the first leg 35. The rebar 33 may be welded around the outer peripheries of the sleeve 25 at desired intervals. In an alternate embodiment, various reinforcing members may be connected to the outer peripheries of the sleeve 25 in various shapes and configurations.

A plurality of lift holes or apertures 39 are located in and extend radially outward through an inner surface 41 of the support sleeve 25. In this particular embodiment, two lift holes 39 are positioned opposite from one another. The lift holes 39 are designed to accept a lifting device or lifting link.

Referring to FIG. 1, the piston portion 16 of the lifting assembly 14 is lowered into the cylinder portion 15 such that the guide plate 27 slides over and down the inner pipe 19 before coming to rest against the base plate 21 (FIG. 5). The concrete slab 11 is then poured, which embeds the rebar 33 and portions of the sleeve assembly 25 within the slab 11. The concrete may be kept from bonding to the concrete pier 13 and the upper ends of the outer pipe 17 by an optional bond breaker layer (not shown).

Referring to FIG. 6, after the cement slab 11 has hardened, a lifting member or solid lifting rod 43 with a smaller diameter than the inner pipe 19 is inserted into the inner pipe 19 and lowered until it makes contact with the base plate 21. The lifting rod 43 extends upwardly a select distance from the base plate 21. The length of the lifting rod 43 can be varied to accommodate various desired heights of the slab 11. After the lifting rod 43 is in place, a lifting device 45 is mounted on the top of the lifting rod 43. In this embodiment, the lifting device 45 is a hydraulic jack mounted on the top of the lifting rod 43. Attachment members or attachment rods 49 are then connected to the lift holes 39 in the sleeve 25 in order to lift the slab 11 to its desired height. The attachment rods 49 are connected on the opposite ends to the hydraulic jack 45.

Referring to FIG. 7, hydraulic fluid pressure is then applied to the jack 45, causing the jack 45 to lift the attachment rods 49 upwards. As the attachment rods 49 move upwards, the slab 11 and the piston portion 16 of the lift assembly 14 also move upwards relative to the cylinder portion 15. As the piston portion 16 moves upwards, the guide plate 27 moves upwards relative to the base plate 21, thereby creating a void 51 between the plates 21, 27. The jack 45 moves the attachment rods 49 upwards until the foundation, slab 11 has been lifted above the ground 12 to the desired height. Once the slab 11 has reached its desired height, a support media is pumped into the void 51 through the ports 31 in the guide plate 27. For example, in an embodiment, the support media may be sand, concrete, or grout. The void 51 is filled with the support media until the guide plate 27 is resting upon the support media, thereby transferring the weight of the slab 11 from the jack 45 to the support media within the void 51.

Referring to FIG. 8, once the slab 11 is secured at its desired height, the attachment rods 49 and the hydraulic jack 45 are removed. If the lifting rod 43 extends above the slab 11, it may be cut to a height so that it does not extend above the slab 11. Alternatively, as shown in this particular embodiment, the lifting rod 43 may be removed. A cap 53 may be inserted into the sleeve 25. In the event that the height of the slab 11 needs to be adjusted, the cap 53 may be removed and the hydraulic jack 45 and the attachment rods 49 may be reconnected. Once the weight of slab 11 is lifted from the support media, the height may be adjusted by raising the piston portion 16 of the lifting assembly 14 to a new desired height, and filling the void between the base plate 21 and the guide plate 27 with additional support media. Once the desired height is reached, as previously illustrated, the slab 11 may be secured in place by lowering the weight of the slab 11 and the sleeve 25 onto the additional support media. If for example, the support media is sand, the slab 11 may be lowered to a new height by removing sand from the void 51. As previously discussed, once the slab 11 has reach its desired height, the hydraulic jack 45 and the attachment rods 49 may be removed and the cap 53 may be reinstalled in the sleeve 25.

The invention has significant advantages. The invention provides a method and apparatus that allows a foundation to be poured on top of soil and subsequently raised to a desired height to eliminate potential problems caused by soil movement and/or problematic soils.

In the drawings and specification, there have been disclosed a typical preferred embodiment of the invention, and although specific terms are employed, the terms are used in a descriptive sense only and not for purposes of limitation. The invention has been described in considerable detail with specific reference to these illustrated embodiments. It will be apparent, however, that various modifications and changes can be made within the spirit and scope of the invention as described in the foregoing specification and as set forth in the following claims. 

1. A system for forming a movable slab foundation, the system comprising: a slab foundation; at least one support pier; at least one housing positioned within the at least one support pier, the at least one housing having an open upper end and a closed lower end; at least one support sleeve positioned within and substantially surrounded by the at least one housing, portions of the at least one support sleeve being encased within the slab foundation, the at least one support sleeve being upwardly moveable relative to the at least one housing; a guide plate connected to the at least one support sleeve, the outer peripheries of the guide plate engaging the inner surfaces of the at least one housing; a cavity defined by the space between the lower surface of the guide plate and the lower end of the at least one housing; and at least one port located in and extending through the guide plate and into the cavity.
 2. The system of claim 1, wherein: the at least one housing is cylindrical in shape; the at least one support sleeve is cylindrical in shape; and the guide plate is circular in shape.
 3. The system of claim 1, wherein the at least one housing further comprises: a first cylinder with an open upper end and a closed lower end; and a second cylinder having a diameter less than the diameter of the first cylinder, the second cylinder being surrounded by the first cylinder, thereby defining an interstitial space between the first cylinder and the second cylinder, and the lower end of the second cylinder being connected to the closed lower end of the first cylinder.
 4. The system of claim 3, wherein: the guide plate further comprises an aperture located in and extending therethrough, the second cylinder extending through the aperture, the guide plate surrounding the second cylinder; and the at least one support sleeve and the guide plate positioned within the interstitial space between the first cylinder and the second cylinder of the at least one housing.
 5. The system of claim 4, further comprising: at least one lifting member surrounded by the second cylinder, the at least one lifting member having a body with first and second ends, the first end abuttingly contacting the closed lower end of the first cylinder, the second end adapted to be coupled to a lifting device to move the at least one support sleeve and the slab foundation axially along the length of the at least one housing.
 6. The system of claim 5, wherein the system further comprises: a lifting device coupled to the second end of the body of the at least one lifting member to move the at least one support sleeve and the slab foundation axially along the length of the at least one housing; and a plurality of attachment members connected to and extending between the least one support sleeve and the lifting device.
 7. The system of claim 1, wherein the at least one support sleeve further comprises: a hollow body with inner and outer surfaces, the outer surface having at least one reinforcing bar connected to and extending outwardly therefrom, the inner surface having at least one aperture located in and extending therethrough and adapted to accept a connecting member.
 8. The system of claim 7, wherein the at least one reinforcing bar further comprises: a first leg connected to the outer surface of the at least one support sleeve and extending parallel to the axis of the at least one support sleeve; and a second leg connected to the lower end of the first leg and extending outwardly and downwardly at angle from the axis of the at least one support sleeve.
 9. The system of claim 1, further comprising: a pumping device connected to the at least one port for pumping a support media into the cavity to support the weight of the at least one support sleeve, the guide plate, and the slab, thereby securing the position of the at least one support sleeve, the guide plate, and the slab relative to the at least one housing.
 10. A system for forming a movable slab foundation, the system comprising: a slab foundation; at least one support pier; a first cylinder with an open upper end and a closed lower end positioned within the at least one support pier; a second cylinder having a diameter less than the diameter of the first cylinder, the second cylinder being surrounded by the first cylinder, thereby defining an interstitial space between the first cylinder and the second cylinder, the lower end of the second cylinder being connected to the closed lower end of the first cylinder; at least one support sleeve, a lower portion of the at least one support sleeve positioned in the interstitial space between the first cylinder and the second cylinder, an upper portion of the at least one support sleeve being encased within the slab foundation, the at least one support sleeve being upwardly moveable relative to the at least one housing; a guide plate connected to the at least one support sleeve and positioned within the interstitial space between the first cylinder and the second cylinder, the outer peripheries of the guide plate engaging the inner surfaces of the first cylinder, an aperture located in and extending through the guide plate, the second cylinder extending through the aperture, the guide plate surrounding the second cylinder; a cavity defined by the space between the lower surface of the guide plate and the closed lower end of the first cylinder; at least one port located in and extending through the guide plate and into the cavity; and a lifting device connected to the at least one support sleeve to move the at least one support sleeve, the guide plate, and the slab foundation axially along the length of the first cylinder and the second cylinder.
 11. The system of claim 10, wherein: the at least one housing is cylindrical in shape; the at least one support sleeve is cylindrical in shape; and the guide plate is circular in shape.
 12. The system of claim 10, wherein the system further comprises: at least one lifting member substantially surrounded by the second cylinder, the at least one lifting member having a body with first and second ends, the first end abuttingly contacting the closed lower end of the first cylinder; and the second end of the body of the at least one lifting member connected to the lifting device.
 13. The system of claim 10, wherein the at least one support sleeve further comprises: a hollow body with inner and outer surfaces, the outer surface having at least one reinforcing bar connected to and extending outwardly therefrom, the inner surface having at least one aperture located in and extending therethrough and adapted to accept a connecting member.
 14. The system of claim 13, wherein the at least one reinforcing bar further comprises: a first leg connected to the outer surface of the at least one support sleeve and extending parallel to the axis of the at least one support sleeve; and a second leg connected to the lower end of the first leg and extending outwardly and downwardly at angle from the axis of the at least one support sleeve.
 15. The system of claim 10, further comprising: a pumping device connected to the at least one port for pumping a support media into the cavity to support the weight of the at least one support sleeve, the guide plate, and the slab foundation, thereby securing the position of the at least one support sleeve, the guide plate, and the slab foundation relative to the first cylinder and the second cylinder.
 16. A method for forming a movable slab foundation, the method comprising: (a) providing a housing with a closed lower end and an open upper end, a guide plate positioned within and surrounded by the housing, the outer peripheries of the guide plate being engaged with the inner surfaces of the housing, a cavity defined by the space between the closed lower end of the housing and the lower surface of the guide plate, a support sleeve connected to the upper surface of the guide plate, and a port located in and extending through the guide plate and into the cavity; (b) placing a support pier below an intended slab foundation area; (c) positioning the housing, the guide plate, and the support sleeve within the support pier; (d) forming a slab foundation such that it encases a portion of the support sleeve; and (e) raising the support sleeve, the guide plate, and the slab foundation upwards relative to the housing to a desired height; and (f) filling the cavity with a support media through the port to support the weight of the support sleeve, the guide plate, and the slab, thereby securing the position of the support sleeve, the guide plate, and the slab relative to the housing.
 17. The method of claim 16, wherein step (a) further comprises: providing an aperture located in and extending through the guide plate; and wherein step (e) further comprises: inserting a lifting member with first and second ends through the aperture, the first end of the lifting member abuttingly contacting the closed lower end of the housing; and connecting a lifting device to the second end of the lifting member and the support sleeve.
 18. The method of claim 16, wherein the support pier is of concrete; and wherein step (c) of the method further comprises allowing the concrete support pier to set up, thereby encasing the housing in the support pier.
 19. The method of claim 16, further comprising after step (f): allowing the support media to set up, thereby securing the position of the support sleeve, the guide plate, and the slab foundation relative to the housing.
 20. The method of claim 16, further comprising after step (f): sealing the port, thereby securing the position of the support sleeve, the guide plate, and the slab foundation relative to the housing. 